Amines are one of the most common classes of organic molecules. They play important roles in a variety of areas, ranging from the pharmaceutical industry to plastics manufacturing.
Current methods for the synthesis of amines generally rely on multi-step processes that convert a variety of amine precursors to the amino (NH2) functional group itself. To date, with the singular exception of two existing methodologies, there has been no general method for the direct synthesis of amines from ammonia. Since ammonia is an inexpensive bulk commodity chemical that is manufactured on a multi-ton scale annually, any process that allows for the direct use of ammonia for the introduction of the amino group is therefore highly desirable.
A robust methodology for the diastereoselective allylation and crotylation of in-situ generated ketimines in the presence of ammonia has recently been developed [Dhudshia, B., Tiburcio, J. and Thadani, A. N. Chem. Commun. 2005, 5551-5553]. The resulting homoallylic amines obtained from the allyl- and crotylboronic acids addition to ketones in methanolic ammonia were reported in good to excellent yields.